39510-74-2Relevant academic research and scientific papers
Zinc acetate-mediated regioselective N-acylation of 1,3-disubstituted selenoureas
Li, Xue,Gan, Bin,Peng, Zhixiang,Mi, Zhisheng,Xie, Yuanyuan
, p. 251 - 254 (2018/06/27)
N-acetylureas were synthesised regioselectively from 1,3-disubstituted selenoureas and zinc acetate. Regioselectivity was dependent on the pKa of the amine attached to the selenourea and occurred towards the amine with the lower pKa. The approach provided a simple, mild and efficient way to construct various N-acetylureas regioselectively in moderate to good yields (53-88%). A plausible mechanism was proposed for the formation of N-acetylureas.
Regioselective acetylate of 1,3-disubstituted selenoureas promoted by recyclable ion-supported hypervalent iodine(III) reagent
Xie, Yuanyuan,Pan, Haixuan
, p. 98 - 105 (2014/01/06)
Abstract A mild, efficient, and environmentally friendly reaction of 1,3-disubstituted selenoureas with a recyclable ion-supported hypervalent iodine(III) reagent produces regioselectively N-acetylureas. This is the first example of ion-supported hypervalent iodine reagent [dibmim]+[BF4] -being employed as an N-acetylating agent. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.
Hypervalent iodine(III)-mediated regioselective N-acylation of 1,3-disubstituted thioureas
Singh,Ghosh, Harisadhan,Murru, Siva,Patel, Bhisma K.
, p. 2924 - 2927 (2008/09/19)
(Chemical Equation Presented) Reaction of asymmetrical 1,3-disubstituted thioureas with diacetoxyiodobenzene (DIB) produces regioselectively N-acetylurea in shorter time. Regioselectivity is dependent on the pKa's of the amine attached to the t
Regioselective synthesis of N-acetylureas by manganese(III) acetate reaction of 1,3-disubstituted thioureas
Mu, Xue-Jun,Zou, Jian-Ping,Qian, Qiu-Feng,Zhang, Wei
, p. 2323 - 2325 (2007/10/03)
Reactions of asymmetrical 1,3-disubstituted thioureas with manganese(III) acetate produce regioselective N-acetylureas. A mechanism for this novel transformation is proposed.
Oxidative rearrangement and cyclisation of N-substituted amidines using iodine(III) reagents and the influence of leaving group on mode of reaction
Ramsden, Christopher A.,Rose, Helen L.
, p. 2319 - 2327 (2007/10/03)
The products of reaction of N-substituted amidines 5 with hypervalent iodine reagents such as (diacetoxyiodo)benzene (DAIB), bis(trifluoroacetoxy)iodobenzene (BFIB) and [methoxy(tosyloxy)-iodo]benzene (MTIB) are determined by the reagent, the amidine substituents and the reaction temperature. C-Alkyl-N-arylamidines 5a-d cyclise in high yield giving benzimidazoles 6 but C,N-dialkyl- and C,N-diaryl-amidines 5e-l rearrange to give products derived from an intermediate carbodiimide. Use of N2-phenylfuran-2-carboximidamide 5j leads to N-(2-furyl)acetamide 15 in good yield, illustrating a convenient route to stable derivatives of highly unstable 2-aminofuran. The rearrangement of C,N-diarylamidines on reaction with DAIB contrasts with the observed formation of benzimidazole when the same precursors are treated with lead tetraacetate (LTA). Evidence is presented to support the view that the mode of reaction is determined by the nature of the leaving group in an imide intermediate 19: very good leaving groups [e.g. PhI, N2, AgCl and PhSO2O- (aq.)] appear to favour rearrangement whereas poorer leaving groups [e.g. Cl-, Me2S, Me3N and PhSO2O- (non-aq.)] favour cyclo-α-elimination.
Rearrangement and cyclo-α-elimination of N-substituted amidines using (acetoxyiodo)benzene
Ramsden, Christopher A.,Rose, Helen L.
, p. 615 - 618 (2007/10/02)
The products of reaction of N-substituetd amidines with (diacetoxyiodo)benzene are determined by the nature of the amidine substituents and the reaction temperature: rearrangement of N2-phenylfuran-2-carboximidamide provides a convenient route to N-(2-furyl)acetamide, whereas N-phenyl C-alkyl formimidamides cyclise to give benzimidazoles in good yield.
Benzenetellurinic Mixed Anhydrides as Mild Oxidizing Agents
Fukumoto, Takahiro,Matsuki, Toshiaki,Hu, Nan Xing,Aso, Yoshio,Otsubo, Tetsuo,Ogura, Fumio
, p. 2269 - 2272 (2007/10/02)
Three benzenetellurinic mixed anhydrides. i. e. benzenetellurinyl acetate, trifluoroacetate, and trifluoromethanesulfonate, have been found to be mild oxidizing agents for various substrates such as thiol, phosphine, acyloin, α-hydroxy ester, catechol, hydroquinone, thiourea, and thioamide.The reactions towards the last two substrates are highly chemoselective, depending on both the reagent and substrate.
Mild Acetylation of Amides, Thiamides, Ureas, and Thioureas Using Methyl Bis(1-naphthyl)bismuthinate in Acetic Acid
Ogawa, Takuji,Miyazaki, Kikuko,Suzuki, Hitomi
, p. 1651 - 1654 (2007/10/02)
Amides, thioamides, ureas, and thioureas were N-acetylated in good yield with acetic acid in the presence of methyl bis(1-naphthyl)bismuthinate at room tempereature.
REACTION OF DIAZOMETHANE WITH SELENOESTERS PREPARATION OF α-(ALKYL- OR ARYLSELENO)METHYL KETONES AND METHYL KETONES
Back, Thomas G.,Kerr, Russell G.
, p. 4759 - 4764 (2007/10/02)
The reaction of diazomethane with a series of selenoesters 1 in the presence of CuI, CuSePh or Cu powder produced α-(alkyl- or arylseleno)methyl ketones 2 in yield of 41-65percent.Methyl ketones 3 and bis(arylseleno)methanes 9 or 14 were formed as by-products.The direct conversion of selenoesters to methyl ketones was accomplished in high yield by the usual reaction with diazomethane, followed by workup with HBr solution.The simultaneous copper-catalyzed reactions of selenoesters 1c and 1i with diazomethane resulted in crossover, with the formation of all four possible α-seleno ketones 2b, 2c, 2h and 2i.A non-concerted mechanism involving attack by the diazo compound upon the acyl carbon atom of an activated selenoester with the formation of a tetrahedral intermediate 11 has been suggested.The reaction of the selenothiocarbamate 4 with diazomethane resulted in 1,3-dipolar cycloaddition to afford 5 instead of insertion into the acyl-selenium bond.
